From 4826af9a07cf243696ce4fc5280a0da4f25c8953 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 5 May 2022 08:27:38 -0700 Subject: [PATCH] i2c: at91: Initialize dma_buf in at91_twi_xfer() [ Upstream commit 6977262c2eee111645668fe9e235ef2f5694abf7 ] Clang warns: drivers/i2c/busses/i2c-at91-master.c:707:6: warning: variable 'dma_buf' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] if (dev->use_dma) { ^~~~~~~~~~~~ drivers/i2c/busses/i2c-at91-master.c:717:27: note: uninitialized use occurs here i2c_put_dma_safe_msg_buf(dma_buf, m_start, !ret); ^~~~~~~ Initialize dma_buf to NULL, as i2c_put_dma_safe_msg_buf() is a no-op when the first argument is NULL, which will work for the !dev->use_dma case. Fixes: 03fbb903c8bf ("i2c: at91: use dma safe buffers") Link: https://github.com/ClangBuiltLinux/linux/issues/1629 Signed-off-by: Nathan Chancellor Reviewed-by: Michael Walle Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-at91-master.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c index 44502024cc10..f74d5ad2f1fa 100644 --- a/drivers/i2c/busses/i2c-at91-master.c +++ b/drivers/i2c/busses/i2c-at91-master.c @@ -609,7 +609,7 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num) unsigned int_addr_flag = 0; struct i2c_msg *m_start = msg; bool is_read; - u8 *dma_buf; + u8 *dma_buf = NULL; dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num);